Merge pull request #4586 from mono/master-roslynfolding

[Ide] Switched to roslyn folding infrastructure.

4 files changed, 144 insertions, 174 deletions

diff --git a/main/src/addins/CSharpBinding/MonoDevelop.CSharp.Parser/CSharpParsedDocument.cs b/main/src/addins/CSharpBinding/MonoDevelop.CSharp.Parser/CSharpParsedDocument.cs
index faff647bc7..4787f4e22d 100644
--- a/main/src/addins/CSharpBinding/MonoDevelop.CSharp.Parser/CSharpParsedDocument.cs
+++ b/main/src/addins/CSharpBinding/MonoDevelop.CSharp.Parser/CSharpParsedDocument.cs
@@ -306,181 +306,9 @@ namespace MonoDevelop.CSharp.Parser
 			}
 		}
 
-		IReadOnlyList<FoldingRegion> foldings;
-		SemaphoreSlim foldingsSemaphore = new SemaphoreSlim (1, 1);
+		static readonly Task<IReadOnlyList<FoldingRegion>> foldings  = Task.FromResult((IReadOnlyList<FoldingRegion>)new FoldingRegion[0]);
 
-		public override Task<IReadOnlyList<FoldingRegion>> GetFoldingsAsync (CancellationToken cancellationToken = default(CancellationToken))
-		{
-			if (foldings == null) {
-				return Task.Run (async delegate {
-					bool locked = false;
-					try {
-						locked = await foldingsSemaphore.WaitAsync (Timeout.Infinite, cancellationToken);
-						if (foldings == null)
-							foldings = (await GenerateFoldings (cancellationToken)).ToList ();
-					} catch (OperationCanceledException) {
-						return new List<FoldingRegion> ();
-					} finally {
-						if (locked)
-							foldingsSemaphore.Release ();
-					}
-					return foldings;
-				});
-			}
-
-			return Task.FromResult (foldings);
-		}
-
-		async Task<IEnumerable<FoldingRegion>> GenerateFoldings (CancellationToken cancellationToken)
-		{
-			return GenerateFoldingsInternal (await GetCommentsAsync (cancellationToken), cancellationToken);
-		}
-
-		IEnumerable<FoldingRegion> GenerateFoldingsInternal (IReadOnlyList<Comment> comments, CancellationToken cancellationToken)
-		{
-			if (cancellationToken.IsCancellationRequested)
-				yield break;
-
-			foreach (var fold in comments.ToFolds ())
-				yield return fold;

-

-			if (cancellationToken.IsCancellationRequested)
-				yield break;
-
-			var visitor = new FoldingVisitor (cancellationToken);
-			if (Unit != null) {
-				try {
-					visitor.Visit (Unit.GetRoot (cancellationToken));
-				} catch (Exception) { }
-			}
-
-			if (cancellationToken.IsCancellationRequested)
-				yield break;
-			foreach (var fold in visitor.Foldings)
-				yield return fold;
-		}
-
-		class FoldingVisitor : CSharpSyntaxWalker
-		{
-			public readonly List<FoldingRegion> Foldings = new List<FoldingRegion> ();
-			CancellationToken cancellationToken;
-
-			public FoldingVisitor (CancellationToken cancellationToken) : base(SyntaxWalkerDepth.Trivia)
-			{
-				this.cancellationToken = cancellationToken;
-			}
-
-			void AddUsings (SyntaxNode parent)
-			{
-				SyntaxNode firstChild = null, lastChild = null;
-				foreach (var child in parent.ChildNodes ()) {

-					cancellationToken.ThrowIfCancellationRequested ();
-					if (child is UsingDirectiveSyntax) {
-						if (firstChild == null) {
-							firstChild = child;
-						}
-						lastChild = child;
-						continue;
-					}
-					if (firstChild != null)
-						break;
-				}
-
-				if (firstChild != null && firstChild != lastChild) {
-					var first = firstChild.GetLocation ().GetLineSpan ();
-					var last = lastChild.GetLocation ().GetLineSpan ();
-
-					Foldings.Add (new FoldingRegion (new DocumentRegion (first.StartLinePosition, last.EndLinePosition), FoldType.Undefined));
-				}
-			}
-
-			public override void VisitCompilationUnit (Microsoft.CodeAnalysis.CSharp.Syntax.CompilationUnitSyntax node)
-			{
-				cancellationToken.ThrowIfCancellationRequested ();
-				AddUsings (node);
-				base.VisitCompilationUnit (node);
-			}
-
-			void AddFolding (SyntaxToken openBrace, SyntaxToken closeBrace, FoldType type)
-			{
-				cancellationToken.ThrowIfCancellationRequested ();
-				openBrace = openBrace.GetPreviousToken (false, false, true, true);
-
-				try {
-					var first = openBrace.GetLocation ().GetLineSpan ();
-					var last = closeBrace.GetLocation ().GetLineSpan ();
-
-					if (first.EndLinePosition.Line != last.EndLinePosition.Line)
-						Foldings.Add (new FoldingRegion (new DocumentRegion (first.EndLinePosition, last.EndLinePosition), type));
-				} catch (ArgumentOutOfRangeException) {}
-			}
-
-			Stack<SyntaxTrivia> regionStack = new Stack<SyntaxTrivia> ();
-			public override void VisitTrivia (SyntaxTrivia trivia)
-			{
-				cancellationToken.ThrowIfCancellationRequested ();
-				base.VisitTrivia (trivia);
-				if (trivia.IsKind (SyntaxKind.RegionDirectiveTrivia)) {
-					regionStack.Push (trivia);
-				} else if (trivia.IsKind (SyntaxKind.EndRegionDirectiveTrivia)) {
-					if (regionStack.Count == 0)
-						return;
-					var regionStart = regionStack.Pop ();
-					try {
-						var first = regionStart.GetLocation ().GetLineSpan ();
-						var last = trivia.GetLocation ().GetLineSpan ();
-						var v = regionStart.ToString ();
-						v = v.Substring ("#region".Length).Trim ();
-						if (v.Length == 0)
-							v = "...";
-						Foldings.Add (new FoldingRegion(v, new DocumentRegion(first.StartLinePosition, last.EndLinePosition), FoldType.UserRegion, true));
-					} catch (ArgumentOutOfRangeException) { }
-				}
-			}
-
-			public override void VisitNamespaceDeclaration (Microsoft.CodeAnalysis.CSharp.Syntax.NamespaceDeclarationSyntax node)
-			{
-				cancellationToken.ThrowIfCancellationRequested ();
-				AddUsings (node);
-				AddFolding (node.OpenBraceToken, node.CloseBraceToken, FoldType.Undefined);
-				base.VisitNamespaceDeclaration (node);
-			}
-
-			public override void VisitClassDeclaration (Microsoft.CodeAnalysis.CSharp.Syntax.ClassDeclarationSyntax node)
-			{
-				cancellationToken.ThrowIfCancellationRequested ();
-				AddFolding (node.OpenBraceToken, node.CloseBraceToken, FoldType.Type);
-				base.VisitClassDeclaration (node);
-			}
-
-			public override void VisitStructDeclaration (Microsoft.CodeAnalysis.CSharp.Syntax.StructDeclarationSyntax node)
-			{
-				cancellationToken.ThrowIfCancellationRequested ();
-				AddFolding (node.OpenBraceToken, node.CloseBraceToken, FoldType.Type);
-				base.VisitStructDeclaration (node);
-			}
-
-			public override void VisitInterfaceDeclaration (Microsoft.CodeAnalysis.CSharp.Syntax.InterfaceDeclarationSyntax node)
-			{
-				cancellationToken.ThrowIfCancellationRequested ();
-				AddFolding (node.OpenBraceToken, node.CloseBraceToken, FoldType.Type);
-				base.VisitInterfaceDeclaration (node);
-			}
-
-			public override void VisitEnumDeclaration (Microsoft.CodeAnalysis.CSharp.Syntax.EnumDeclarationSyntax node)
-			{
-				cancellationToken.ThrowIfCancellationRequested ();
-				AddFolding (node.OpenBraceToken, node.CloseBraceToken, FoldType.Type);
-				base.VisitEnumDeclaration (node);
-			}
-
-			public override void VisitBlock (Microsoft.CodeAnalysis.CSharp.Syntax.BlockSyntax node)
-			{
-				cancellationToken.ThrowIfCancellationRequested ();
-				AddFolding (node.OpenBraceToken, node.CloseBraceToken, node.Parent is MemberDeclarationSyntax ? FoldType.Member : FoldType.Undefined);
-				base.VisitBlock (node);
-			}
-		}
+		public override Task<IReadOnlyList<FoldingRegion>> GetFoldingsAsync (CancellationToken cancellationToken = default (CancellationToken)) => foldings;
 
 		SemaphoreSlim errorLock = new SemaphoreSlim (1, 1);
 
diff --git a/main/src/core/MonoDevelop.Ide/ExtensionModel/MonoDevelop.Ide.addin.xml b/main/src/core/MonoDevelop.Ide/ExtensionModel/MonoDevelop.Ide.addin.xml
index e881821723..3424347b8d 100644
--- a/main/src/core/MonoDevelop.Ide/ExtensionModel/MonoDevelop.Ide.addin.xml
+++ b/main/src/core/MonoDevelop.Ide/ExtensionModel/MonoDevelop.Ide.addin.xml
@@ -318,6 +318,7 @@
 		<Class class = "MonoDevelop.Ide.Editor.Extension.BraceMatcherTextEditorExtension" />
 		<Class class = "MonoDevelop.Ide.Editor.Extension.DefaultCommandTextEditorExtension" />
 		<Class class = "MonoDevelop.Ide.Editor.Extension.FoldingTextEditorExtension" />
+		<Class class = "MonoDevelop.Ide.Editor.Extension.BlockStructureFoldingTextEditorExtension" />
 		<Class class = "MonoDevelop.Ide.Editor.Extension.ErrorHandlerTextEditorExtension" />
 		<Class class = "MonoDevelop.Ide.Editor.Extension.AutoInsertBracketTextEditorExtension" />
 		<Class class = "MonoDevelop.Ide.Editor.Extension.HighlightUrlExtension" />
diff --git a/main/src/core/MonoDevelop.Ide/MonoDevelop.Ide.Editor.Extension/BlockStructureFoldingTextEditorExtension.cs b/main/src/core/MonoDevelop.Ide/MonoDevelop.Ide.Editor.Extension/BlockStructureFoldingTextEditorExtension.cs
new file mode 100644
index 0000000000..6727ea5c80
--- /dev/null
+++ b/main/src/core/MonoDevelop.Ide/MonoDevelop.Ide.Editor.Extension/BlockStructureFoldingTextEditorExtension.cs
@@ -0,0 +1,140 @@
+//
+// BlockStructureFoldingTextEditorExtension.cs
+//
+// Author:
+//       Mike Krüger <mikkrg@microsoft.com>
+//
+// Copyright (c) 2018 Microsoft Corporation. All rights reserved.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a copy
+// of this software and associated documentation files (the "Software"), to deal
+// in the Software without restriction, including without limitation the rights
+// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+// copies of the Software, and to permit persons to whom the Software is
+// furnished to do so, subject to the following conditions:
+//
+// The above copyright notice and this permission notice shall be included in
+// all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+// THE SOFTWARE.
+
+using System;
+using System.Collections.Generic;
+using System.IO;
+using System.Threading;
+using System.Threading.Tasks;
+using Gtk;
+using MonoDevelop.Core;
+using MonoDevelop.Core.Text;
+using MonoDevelop.Ide.Editor.Highlighting;
+using MonoDevelop.Ide.TypeSystem;
+using Microsoft.CodeAnalysis.Structure;
+using System.Collections.Immutable;
+
+namespace MonoDevelop.Ide.Editor.Extension
+{
+	class BlockStructureFoldingTextEditorExtension : TextEditorExtension
+	{
+		CancellationTokenSource src = new CancellationTokenSource ();
+		bool isDisposed;
+
+		protected override void Initialize ()
+		{
+			DocumentContext.DocumentParsed += DocumentContext_DocumentParsed;
+		}
+
+		public override void Dispose ()
+		{
+			if (isDisposed)
+				return;
+			isDisposed = true;
+			CancelDocumentParsedUpdate ();
+			DocumentContext.DocumentParsed -= DocumentContext_DocumentParsed;
+			base.Dispose ();
+		}
+
+		void CancelDocumentParsedUpdate ()
+		{
+			src.Cancel ();
+			src = new CancellationTokenSource ();
+		}
+
+		async void DocumentContext_DocumentParsed (object sender, EventArgs e)
+		{
+			CancelDocumentParsedUpdate ();
+			var analysisDocument = DocumentContext.AnalysisDocument;
+			if (analysisDocument == null || !Editor.Options.ShowFoldMargin)
+				return;
+			var caretLocation = Editor.CaretOffset;
+
+			var outliningService = BlockStructureService.GetService (analysisDocument);
+			if (outliningService == null)
+				return;
+			var token = src.Token;
+			var blockStructure = await outliningService.GetBlockStructureAsync (analysisDocument, token).ConfigureAwait (false);
+			UpdateFoldings (Editor, blockStructure.Spans, caretLocation, false, token);
+		}
+
+		static void UpdateFoldings (TextEditor Editor, ImmutableArray<BlockSpan> spans, int caretOffset, bool firstTime = false, CancellationToken token = default (CancellationToken))
+		{
+			try {
+				var foldSegments = new List<IFoldSegment> ();
+
+				foreach (var blockSpan in spans) {
+					if (token.IsCancellationRequested)
+						return;
+					if (!blockSpan.IsCollapsible)
+						continue;
+					var type = FoldingType.Unknown;
+					switch (blockSpan.Type) {
+					case BlockTypes.Member:
+						type = FoldingType.TypeMember;
+						break;
+					case BlockTypes.Type:
+						type = FoldingType.TypeDefinition;
+						break;
+					case BlockTypes.Comment:
+						type = FoldingType.Comment;
+						break;
+					default:
+						type = FoldingType.Unknown;
+						break;
+					}
+					var start = blockSpan.TextSpan.Start;
+					var end = blockSpan.TextSpan.End;
+					var marker = Editor.CreateFoldSegment (start, end - start);
+					if (marker == null)
+						continue;
+					foldSegments.Add (marker);
+					marker.CollapsedText = blockSpan.BannerText;
+					marker.FoldingType = type;
+					//and, if necessary, set its fold state
+					if (firstTime) {
+						// only fold on document open, later added folds are NOT folded by default.
+						marker.IsCollapsed = blockSpan.IsDefaultCollapsed;
+						continue;
+					}
+					if (blockSpan.TextSpan.Contains (caretOffset))
+						marker.IsCollapsed = false;
+				}
+				if (firstTime) {
+					Editor.SetFoldings (foldSegments);
+				} else {
+					Application.Invoke ((o, args) => {
+						if (!token.IsCancellationRequested)
+							Editor.SetFoldings (foldSegments);
+					});
+				}
+			} catch (OperationCanceledException) {
+			} catch (Exception ex) {
+				LoggingService.LogError ("Unhandled exception in ParseInformationUpdaterWorkerThread", ex);
+			}
+		}
+	}
+}
\ No newline at end of file
diff --git a/main/src/core/MonoDevelop.Ide/MonoDevelop.Ide.csproj b/main/src/core/MonoDevelop.Ide/MonoDevelop.Ide.csproj
index b21db9d955..750687104d 100644
--- a/main/src/core/MonoDevelop.Ide/MonoDevelop.Ide.csproj
+++ b/main/src/core/MonoDevelop.Ide/MonoDevelop.Ide.csproj
@@ -9646,6 +9646,7 @@
     <Compile Include="Gui\MonoDevelop.Ide.Projects.SelectReferenceDialog.cs" />
     <Compile Include="Gui\MonoDevelop.Ide.SelectEncodingsDialog.cs" />
     <Compile Include="Gui\MonoDevelop.Ide.StandardHeader.StandardHeaderPolicyPanelWidget.cs" />
+    <Compile Include="MonoDevelop.Ide.Editor.Extension\BlockStructureFoldingTextEditorExtension.cs" />
   </ItemGroup>
   <ItemGroup>
     <None Include="Makefile.am" />